The concept of unit dose packaging is attractive for certain pharmaceutical applications because it conveniently allows systematic dispensing of single doses, and also enables the user to track the consumption of doses according to the prescribed schedule. A feature of such packaging is that it is sturdy enough to be opened and closed numerous times until the course of medication is completed. Examples of such packaging are described in commonly assigned U.S. Pat. No. 6,047,829 (Johnstone). The Johnstone patent relates to a unit dose paperboard package that includes an outer paperboard sleeve and an inner paperboard slide card that is lockably retained within the sleeve. The sleeve includes a plurality of side panels operatively connected to each other such that one of said plurality of side panels includes a first inner slide card releasing means, and another of said side panels includes a second inner slide card releasing means, such that the inner slide card retaining and releasing means are located substantially adjacent to said unit dose dispensing means.
Child resistance is a feature particularly desired for unit dose pharmaceutical packaging, and is mandated by the Poison Prevention Packaging Act of 1970. Guidelines are prescribed for packaging to satisfy the criteria for child resistance under the statute. For example, a child resistance (CR) rating of F=1 requires that a random sampling of the subject packages not be compromised by an age specific test pool of children at a failure rate of greater than 10%. This general guideline is designed to ensure that the package maintains sufficient integrity against tampering by children.
An objective of the present invention is to provide a reinforced unit dose package having, in particular, a durable locking feature. Another objective of the invention is to provide a unit dose packaging system that is easy to open while meeting and maintaining the desired child resistance criteria throughout its use life. These and other objectives, including the improvement of aesthetic enhancement and shipping and packaging stability are met by the various embodiments of the present invention.